/***************************************************************************************************
 * Copyright (c) 2017-2021, NVIDIA CORPORATION.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 *modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright notice,
 *this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *notice, this list of conditions and the following disclaimer in the
 *documentation and/or other materials provided with the distribution.
 *     * Neither the name of the NVIDIA CORPORATION nor the names of its
 *contributors may be used to endorse or promote products derived from this
 *software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY DIRECT,
 *INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 *OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 *EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 **************************************************************************************************/
/*! \file

  \brief Epilogue for threadblock scoped GEMMs using Tensor Ops.

  The epilogue rearranges the result of a matrix product through shared memory
  to match canonical tensor layouts in global memory. Epilogues support
  conversion and reduction operations.

*/

#pragma once

#include "cutlass/cutlass.h"
#include "cutlass/numeric_types.h"
#include "cutlass/array.h"

#include "cutlass/gemm/gemm.h"

#include "cutlass/epilogue/threadblock/default_epilogue_tensor_op.h"
#include "cutlass/epilogue/threadblock/default_epilogue_volta_tensor_op.h"
#include "cutlass/epilogue/threadblock/epilogue.h"
#include "cutlass/epilogue/threadblock/epilogue_with_reduction.h"

////////////////////////////////////////////////////////////////////////////////

namespace cutlass {
namespace epilogue {
namespace threadblock {

////////////////////////////////////////////////////////////////////////////////

/// Defines sensible defaults for epilogues for TensorOps.
template <typename Shape, typename WarpMmaTensorOp, int PartitionsK,
          typename ElementOutput, typename OutputOp, typename ReductionOp,
          int ElementsPerAccess>
struct DefaultEpilogueWithReductionTensorOp {
    /// Use defaults related to the existing epilogue
    using Base = DefaultEpilogueTensorOp<Shape, WarpMmaTensorOp, PartitionsK,
                                         OutputOp, ElementsPerAccess>;

    /// Additional tensor tile iterator
    using TensorTileIterator =
            cutlass::epilogue::threadblock::PredicatedTileIterator<
                    typename Base::OutputTileThreadMap,
                    typename OutputOp::ElementTensor>;

    using OutputTileIterator =
            cutlass::epilogue::threadblock::PredicatedTileIterator<
                    typename Base::OutputTileThreadMap, ElementOutput>;

    /// Define the epilogue
    using Epilogue = EpilogueWithReduction<
            Shape, WarpMmaTensorOp, PartitionsK, OutputTileIterator,
            TensorTileIterator, typename WarpMmaTensorOp::ElementC,
            typename Base::AccumulatorFragmentIterator,
            typename Base::WarpTileIterator, typename Base::SharedLoadIterator,
            typename Base::OutputOp, ReductionOp, typename Base::Padding>;
};

////////////////////////////////////////////////////////////////////////////////

/// Defines sensible defaults for epilogues for TensorOps.
template <typename Shape, typename WarpMmaTensorOp, int PartitionsK,
          typename ElementOutput, typename OutputOp, typename ReductionOp,
          int ElementsPerAccess>
struct DefaultEpilogueWithReductionVoltaTensorOp {
    /// Use defaults related to the existing epilogue
    using Base =
            DefaultEpilogueVoltaTensorOp<Shape, WarpMmaTensorOp, PartitionsK,
                                         OutputOp, ElementsPerAccess>;

    /// Additional tensor tile iterator
    using TensorTileIterator =
            cutlass::epilogue::threadblock::PredicatedTileIterator<
                    typename Base::OutputTileThreadMap,
                    typename OutputOp::ElementTensor>;

    using OutputTileIterator =
            cutlass::epilogue::threadblock::PredicatedTileIterator<
                    typename Base::OutputTileThreadMap, ElementOutput>;

    /// Define the epilogue
    using Epilogue = EpilogueWithReduction<
            Shape, WarpMmaTensorOp, PartitionsK, OutputTileIterator,
            TensorTileIterator, typename WarpMmaTensorOp::ElementC,
            typename Base::AccumulatorFragmentIterator,
            typename Base::WarpTileIterator, typename Base::SharedLoadIterator,
            typename Base::OutputOp, ReductionOp, typename Base::Padding>;
};

////////////////////////////////////////////////////////////////////////////////

}  // namespace threadblock
}  // namespace epilogue
}  // namespace cutlass

////////////////////////////////////////////////////////////////////////////////
